The one-day event, which takes place on Sunday, will see 36 competitors challenged in five disciplines across three different venues over an 11-hour period.
"For us it is still a little bit difficult because we have to keep the balance between enjoying the atmosphere and still be focussed and well-trained because we still have our competition coming up so the day is packed," said Germany's Lena Schoeneborn, who won gold in Beijing in 2008.
"Maybe next time we can increase the event by having the medals awarded at the closing ceremony?," she joked.
The men's modern pentathlon, celebrating its Olympic centenary, takes place a day earlier on Saturday.
Its new format begins with a round-robin fencing competition followed by a 200 metres swim. Then comes show jumping and a combined shoot/run where athletes take five shots at a target before running 1000m, repeating the procedure three times.
The combined event is making its Olympic debut, having been introduced to the sport in 2009 in a bid to make it more exciting for spectators.
The competitor who has amassed the most points in the three earlier events goes first and the rest of the field is staggered behind, with the first across the finish line taking gold.
"When during the shoot/run the places are changing, there is some drama, it is much more exciting," said Klaus Schormann, President of the International Modern Pentathlon Union (UIPM).
Laser shooting, rather than air pellet pistols, will also be used for the first time at an Olympics, having been introduced last year to make the event safer and more environmentally friendly.
Although Russia's Andrei Moiseev, seeking to win a third successive gold, is among the favourites in the men's event, Schoeneborn believes the changes the sport has undergone since Beijing will make it hard to defend her title.
"I won in 2008 and I was really confident with what I was doing and suddenly something big changed and I had to adapt, my technique especially. We had to train differently .. I think I would need more time to really adjust," she said.
"For me this is a completely new competition, a different competition... so far I don't have the title of 2008 too much in mind. So it is everything back to zero."
While organisers busy themselves transforming the equestrian venue at Greenwich Park, which will host the pentathlon's riding and combined events, the competitors will have to try and stay away from the party atmosphere of the Olympic village as other events finish and athletes unwind.
"So far we didn't get in touch with any intense partying," said 26-year-old Schoeneborn. "It was quiet enough to get some sleep so I hope it will stay that way."